Conveying apparatus for furnaces



Feb. 20, 1951 H. OTTINGER ET AL CONVEYING APPARATUS FOR FURNACES 3 Sheets-Sheet 1 Filed Dec. 3, 1946 Zinnentor HOW/1] Utt/nger and 0/372 J Kirchner Then ' attorney Feb. 20, 1951 H. OTTINGER ETAL 2,542,878

CONVEYING APPARATUS FOR FURNACES Filed D60. 3, 1946 3 Sheets-Sheet 2 x fig. 5.

. Snve l r Harry Uit/nger and "o Geo/ye J Kirchner Thri r attorney Feb. 20, 1951 QTTINGER ETAL 2,542,878

CONVEYING APPARATUS FOR FURNACES Filed Dec. 3, 1946 3 Sheets-Sheet 3 fig. 5.

46 EI I Zimwntor Harry Owing er and 8" George J. Kirchner Thur flmorncu Patented Feb. 20, 1951 CONVEYING APPARATUS FOR FURNACES Harry Ottinger, McKeespor-t, Pa., and George J. Kirchner, Lorain, Ohio, assignors to National Tube Company, a corporation of New Jersey Application December 3, 1946, Serial No. 713,626

3 Claims. (Cl. 308-203) This invention relates to a conveying apparatus such as is used for conveying pipe and the like through heating furnaces.

In the manufacture of steel pipe, for example, the workpiece is passed through heating furnaces while supported on, and moved by, powerdriven rolls. Usually these conveyor rolls are water-cooled, and sometimes they are supported exterio'rly of the furnace into which they extend by outboard bearings. Such conveyor rolls must possess sufiicient strength to carry the load of the moving workpiece and to withstand the additional stresses set up by the high temperature conditions within the furnace. Failure of a conveyor roll introduces a number of problems. An unexpected crack or failure in the body of the conveyor roll would permit the cooling water to escape and flow into the hot interior of the furnace. In case of a roll failure, it might not be convenient to shut down the mill and remove the damaged roll, wherefore it is sometimes decided to run the conveyor roll without the benefit of water cooling. The heat resulting from such an expedient is, of course, very hard on the bearings.

In order to obviate the foregoing disadvantages it is sometimes decided to disconnect a damaged conveyor roll from its driving medium and simply permit the said roll to function as an idle roll, postponing until some future convenient time the substitution of a new or spare role.

Because of the foregoing difliculties conveyor rolls of the type referred to usually have a comparatively short length of service.

It is among the objects of the present invention to provide a conveying apparatus for furnaces which obviates the difficulties described.

Another object is the provision of a conveying apparatus for furnaces which is highly efficient and durable in service and one which may be easily dismantled, repaired and replaced.

The invention, then, comprises the features hereinafter described and as particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative of several of the number of Ways in which the principles of the invention may be employed.

In said drawings:

Figure 1 is a fragmentary plan of a series of water-cooled conveyor rolls shown as extending into a heatin furnace, the latter being shown fragmentarily and in dotted lines;

Figure 2 is an elevation of a modification of the showing of Figure 1;

Figure 3 is an enlarged elevation, partly in section, taken at a point intermediate the length of the furnace;

Figure 4 is an end view, partly in section, of a portion of the showing of Figure 3;

Figure 5 is an elevation, partly in section, of an operating detail; and

Figure 6 is a sectional view of the water-cooled roll per se.

Referring more particularly to the drawings, the numeral 2 designates a furnace of elongate construction through which it is desired to continuously pass the workpieces to be heat treated, for example steel pipe, as hereinbefore mentioned. Such a furnace may be used for annealing, warm-working, etc. In the operation of the continuous furnace 2, it is essential that the workpiece be supported at a plurality of points throughout the length of the furnace. For this reason it is necessary to so dispose a number of water-cooled conveyor rolls as to extend into the furnace 2 through suitably spaced apertures 3.

The water-cooled conveyor roll of the present invention comprises a tubular body portion 4, an outward hollow extension 5 having a pipereceiving groove 6 therein, and an inward extension 8 in the form of a cap or closure. Preferably, but not necessarily, all three of the elements 4, 5 and 8 are steel castings which may be telescoped together in the manner shown in Figure 6. In addition, the inward extension 8 has an aperture [0 through which there extends a tube I I for the purpose of conveying cooling water to the interior of the water-cooled conveyor roll.

Referring still to Figure 6, the mid-portion of the tubular body portion 4 to the conveyor roll is provided with a pair of spaced annular rings 13 which are attached in any suitable manner, for example by welding, shrink-fitting, etc.

As shown in Figure 2, each of the water-cooled conveyor rolls is supported by, and extends from, a bearing housing l5, one of the latter being disposed opposite each of the apertures 3 in the side wall of the furnace 2.

To the top of each of the bearing housings l5 there is connected a hinged cap IS. The bottom of each of the bearing housings l5 carries a lower rocker arm l1, while a similar rocker arm [8 is carried on the bottom of each of the hinged caps I6. Each of these rocker arms l1 and I8 carries a pair of spaced grindstone type alloy auaeva steel bushed roller bearings, the same being generally indicated at 20. Finished races (not shown) on the tubular body portion 4 of each of the water-cooled conveyor rolls are engaged by the grindstone type roller bearings 20 and cause the said rolls to rotate smoothly. The spaced annular rings [3 act as a thrust collar for the opposed grindstone type bearing assemblies in one of the housings I5 opposite each of the apertures 3 in the furnace 2 (see Figure 2), thereby preventing lateral shifting of the water-cooled rolls within the furnace.

To each of the water-cooled rolls there is keyed a baflle plate 2| which shields the adjacent grindstone bearings 20 from the hot gases which tend to escape from the furnace through the apertures 3.

According to the foregoing construction and arrangement, each .of the water-cooled rolls is provided with cantilever type bearings which are disposed entirely exteriorly of the furnace 2 and are protected against the escape of the furnace gases through the apertures through which the water-cooled rolls extend. In addition, each of the water-cooled rolls is supported and aligned by an 8-point bearing comprising four rocker arms l|-l8, of which each carries two spaced grindstone type bushed alloy steel roller bearings. In the case of each of the water-cooled rolls, two of the rocker arms are disposed below its horizontal center line and two are disposed above the said center line. The substantial spacing of each cooperating pair of upper and lower bearing assemblies lends rigidity to the water-cooled rolls supported thereby. The hinged caps l6 permit expeditious removal of the adjacent watercooled roll without disturbing any of the other parts of the apparatus.

The water-cooled rolls may be driven in any suitable manner, as for example by attaching a sprocket 24 to each of the water-cooled rolls and connecting the same through a chain 25 with a sprocket 26 of an adjacent speed-reducing unit 28, all of the said units being connected by a line shaft 29.

A motor 30 with shaft extension on both ends thereof may be inserted directly in the line shaft 29, and driving through the individual speed-reducing units 28 power may be diverted laterally from the driving shaft to each of the 'water-' cooled rolls at suitable speeds through the said chain and sprocket drives.

According to the immediately foregoing construction and arrangement any individual speedreducing unit 28 may be removed from the driving mechanism through the medium of flexible couplings and a straight section of the motor driven line shaft 29 substituted therefor, thus keeping the line shaft intact. Or, if desired, the chain 25 may be removed from the sprockets and any one of the water-cooled rolls taken out of operation. v

Referring to Figure 2, the water-cooled rolls may, if desired, be driven through the chain and sprocket arrangement hereinbefore described, but from adjacently disposed individual motors 32.

"It is proposed to so dispose the water-cooled rolls that the same may be elevated and lowered in a unitary fashion to thereby accommodate workpieces of various sizes. More specifically, such supporting instrumentalities may take the form of a pair of spaced parallel rails 34 which extend throughout the length of the furnace and provide support for the bearing housings IS. The longitudinally extending rails 34 carry at suitable intervals cheek plates 38, a longitudinally movable wedge 31 being disposed between each of the cheek plates and a bearing pad 38 which is disposed immediately therebe- The longitudinally movable wedges t]! are unitarily moved through a connecting rod 39 to which motion is imparted by a threaded nut 41, the latter in turn receiving rotation from a conveniently disposed reversible electric motor 42. In order to maintain the stability of the construction after the series of wedges 31 has been so disposed as to properly elevate the watercooled rolls, the supporting instrumentalities are locked in position upon the wedges by a series of spaced posts 45 which are firmly anchored or fixed to the bearing pads 38, the threaded upper ends of the posts being threaded to receive suitable 'heavy threaded nuts 46. When these nuts 46 engage the threaded upper ends of the spaced posts 45, premature starting of the reversible electric motor 42 (and operation of the series of wedges 31) may be prevented by utilizing a series of safety devices, each of which may take the form of a limit switch 48 having a plunger 49 which engages one of the heavy threaded nuts, the control circuit (not shown) being such that the said reversible electric motor 42 may be started only after all of the holddown nuts are fully relieved or backed away.

While we have shown and described certain specific embodiments of the present invention, it will be readily understood by those skilled in the art that we do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of the invention as defined in the appended claims.

We claim:

1. A bearing structure for rotatably supporting a conveyor roll as a cantilever, comprising a pair of spaced bearing housings, each housing having a pair of vertically spaced rocker arms pivoted therein, each rocker arm having a plurality of bearing rollers journaled thereon, the rollers of said two housings being adapted to engage races spaced along the length of said roll.

2. A bearing structure as defined in claim 1 characterized by each of said housings including a cap pivoted to one side thereof, the upper of said rocker arms being mounted on said cap.

3. A bearing structure as defined in claim 1 characterized by the rollers in at least one of said housings cooperating with thrust-sustaining means on said conveyor rollto restrain axial movement thereof.

HARRY OTTINGER. GEORGE J. KIRCHNER.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS 

